Flutter App Development —
Pixel-Perfect. Every Platform.
One Dart codebase. iOS, Android, and web — all pixel-perfect, all 60fps. Flutter's custom rendering engine delivers design fidelity that other cross-platform frameworks simply can't match.
Flutter Development Services
Cross-Platform Apps (iOS + Android)
One Flutter codebase delivers native-feeling iOS and Android apps simultaneously. Flutter's Impeller rendering engine draws every pixel itself — no platform UI widgets — which means identical appearance on both platforms and design that looks exactly like the Figma file.
Flutter + Web
Flutter targets the web alongside mobile. One Dart codebase can produce your iOS app, Android app, and a progressive web app. Ideal for internal enterprise tools, admin dashboards, and products that need all three surfaces with consistent UI logic.
Complex Animation & Motion UI
Flutter's custom rendering engine makes smooth, complex animations significantly easier than in React Native. We use Flutter's AnimationController, Hero transitions, and Rive animations for apps where motion design is a first-class requirement.
Fintech & Financial Apps
Flutter is widely used in fintech — Google Pay is built on Flutter. We build financial dashboards, portfolio trackers, payment apps, and investment platforms with biometric auth, real-time data, and end-to-end encryption.
Flutter + Supabase / Firebase Backend
Real-time data, user auth, cloud functions, and file storage using Supabase (PostgreSQL-backed) or Firebase (Firestore). We architect the full backend data model, security rules, and API layer — not just wire up the Flutter SDK.
Flutter App Performance Audit
Existing Flutter app with frame drops or high memory usage? We profile with Flutter DevTools, identify jank causes (expensive build methods, layout thrashing, large image decode), and fix them. Target: 60fps on mid-range Android devices.
How We Build Flutter Apps
Riverpod for State Management
We use Riverpod 2.x (or Bloc for larger teams) for state management — not Provider (deprecated) or setState spaghetti. Riverpod's compile-safe providers and code generation make large Flutter apps maintainable.
Go Router for Navigation
GoRouter (Flutter's officially recommended navigation package) with deep linking, redirect guards, and typed routes. Authentication-gated routes, bottom tab navigation, and nested navigation set up correctly from day one.
Material Design 3 + Custom Design System
We implement Material Design 3 theming or a fully custom design system from your Figma file using Flutter's ThemeData. Dynamic colour (Material You) supported. Dark mode is built in from the start, not added as an afterthought.
Dart Code Quality
Strong-mode Dart with flutter_lints enforced. We follow the official Dart style guide, use freezed for immutable data classes, and json_serializable for API models. The codebase is tested with flutter_test and integration_test.
Technology Stack
What Our Flutter Clients Say
"The Flutter app Sigill built for our fintech product is absolutely pixel-perfect. Every animation and transition works at 60fps even on mid-range Android. Our designer said it looks exactly like the Figma prototype — rare to hear that."
"We needed iOS, Android, and a web admin dashboard from one codebase. Sigill built the whole thing in Flutter and it all looks and works identically. Saved us months vs building three separate apps."
"Our health app needed complex animations on the onboarding and data visualisation screens. Sigill's Flutter team delivered motion design I genuinely didn't think was possible in a cross-platform app. Exceptional work."
Frequently Asked Questions
Choose Flutter when: (1) pixel-perfect UI fidelity is critical — Flutter draws its own pixels via the Impeller engine, (2) you need to target iOS, Android, and web from one codebase, (3) your app has complex animations or custom UI components, (4) your team prefers strongly-typed Dart over JavaScript. Choose React Native when: your team has React experience, you need to integrate many JavaScript ecosystem libraries, or you're building a Shopify-connected commerce app (Shopify's mobile SDK is React Native-based).
A simple Flutter app with 6–8 screens and a Firebase backend typically costs ₹3,50,000–₹7,00,000. A mid-complexity app with custom animations, real-time features, and payment integration costs ₹8,00,000–₹16,00,000. A complex fintech or enterprise app costs ₹16,00,000+. All projects are fixed-price.
Yes — Flutter's Impeller rendering engine (replacing Skia) achieves consistent 60fps and 120fps on supported devices. Because Flutter draws its own pixels rather than using platform UI widgets, it avoids many of the performance overhead sources that affect React Native. Google Pay, Alibaba's Xianyu (50M+ users), and eBay Motors are all built on Flutter.
Yes — one Flutter/Dart codebase can target iOS, Android, and web. The web build runs on Flutter's CanvasKit renderer for pixel-perfect consistency with mobile, or the HTML renderer for better SEO (limited UI fidelity). We recommend Flutter web for admin dashboards, internal tools, and companion web portals — not for public-facing marketing sites where web-native technologies are better.
We use Riverpod 2.x for most projects — it's compile-safe, testable, and handles async state cleanly with AsyncValue. For larger teams or projects where existing engineers are already familiar with Bloc, we use flutter_bloc. We avoid outdated patterns like Provider (deprecated) and bare setState beyond widget-local state.
Yes — Razorpay has an official Flutter plugin. We integrate the full payment flow including order creation on the backend, the Razorpay checkout modal, payment verification via webhook, and refund handling. We test across all Indian payment methods: UPI, cards, netbanking, wallets, and EMI.
No — we write all Flutter code by hand. FlutterFlow is a visual builder that produces messy, hard-to-maintain generated code. Hand-coded Flutter with proper state management, clean architecture, and test coverage is faster to iterate on, easier to extend, and significantly more maintainable.
A basic Flutter app on 6–8 screens with Firebase backend takes 8–12 weeks. A medium app with custom animations, real-time data, and payment integration takes 14–20 weeks. We deliver sprint builds every two weeks so you see the app working on device throughout development.
Yes — Flutter builds are compiled to native ARM code for iOS and Android. We handle the Xcode archive, TestFlight, and App Store submission for iOS, and the signed AAB, Play Store internal testing, and production release for Android. App Store review for Flutter apps typically takes 1–3 days.
Yes — Flutter releases major SDK updates several times a year, and each update can require dependency updates and occasionally breaking API changes. We offer monthly retainer support covering SDK version upgrades, dependency security patches, Sentry crash monitoring, and feature development.
Let's Build Your Flutter App
Tell us what you're building — platforms, target users, and key features. We'll send a fixed-price proposal within 24 hours.